Why is japanese chestnut resistant to Phytophthora cinnamomi, "the biological bulldozer"?

Methods

Summary

The project has different approaches: a breeding approach, through controlled crosses, a transcriptomic approach and histopathology. The controlled crosses aim to create an hybrid F1 population between the  European chestnut, very susceptible to P.cinnamomi and the Japanese chestnut, resistant,segregating for the trait. In this segregant population we can map loci of resistance ( QTL - Quanatitative Trait Loci) using genetic linkage mapping. By now we have a F1 and the first F2 population, that resulted from the open pollination between the F1 individuals. At the same time we are using a transcriptomic approach where we are identifying candidate genes of resistance in the root transcriptomes of the resistant host, the Japanese chestnut, infected and non infected with P.cinnamomi. In the histopathology approach we are comparing the progression of P.cinnamomi in the two parents, the resistant C.crenata, the japanese chestnut and  the susceptible C.sativa. The results obtained so far are very encouraging with 3 papers already published and two in preparation.

Papers published

Santos C, Zhebentyayeva T,  Serrazina S, Nelson C.Dana , Costa R ( 2015) - Development and characterization of EST-SSR markers for mappingreaction to Phytophthora cinnamomi in Castanea spp. Scientia Horticulturae. 194: 181–187 doi.org/10.1016/j.scienta.2015.07.043

 Serrazina S, Santos C, Machado H, Pesquita C,  Vicentini R, Pais V, Sebastina M, Costa R (2015) - Castanea root transcriptome in response to Phytophthora cinnamomi challenge. Tree Genetics and Genomes. doi: 10.1007/s11295-014-0829-7.

Santos C, Machado, H, Correia I, Gomes F, Gomes-Laranjo J, e Costa R (2015) - Phenotyping Castanea hybrids for Phytophthora cinnamomi resistance. Plant Pathology doi: 10.1111/ppa.12313.